transforming-growth-factor-beta and Root-Resorption

Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been shown to stimulate alveolar bone and cementum formation in periodontal defects but not a functionally oriented periodontal ligament (PDL). Subcutaneous and intramuscular implants of BMP-12 have been shown to induce tendon formation and ligament-like tissue. The objective of this study was to evaluate rhBMP-12 for periodontal regeneration, in particular PDL formation.. Six young adult Hound Labrador mongrel dogs were used. Routine supraalveolar periodontal defects were created around the mandibular premolar teeth. Three animals received rhBMP-12(0.04 mg/ml) in an absorbable collagen sponge (ACS) carrier vs. rhBMP-12(0.2 mg/mL)/ACS in contralateral defects. Three animals received rhBMP-12(1.0 mg/ml)/ACS vs. rhBMP-2(0.2 mg/ml)/ACS (total implant volume/defect approximately 1 ml). The animals were euthanized 8 weeks postsurgery and block biopsies were processed for histometric analysis.. Bone regeneration appeared increased in sites receiving rhBMP-2/ACS compared to sites receiving rhBMP-12/ACS. Cementum regeneration was similar comparing sites implanted with rhBMP-2/ACS to sites implanted with rhBMP-12/ACS. In contrast, sites receiving rhBMP-12/ACS exhibited a functionally oriented PDL bridging the gap between newly formed bone and cementum whereas this was a rare observation in sites receiving rhBMP-2/ACS. Ankylosis appeared increased in sites receiving rhBMP-2/ACS compared to those receiving rhBMP-12/ACS.. The outcomes of this study suggest that rhBMP-12 may have significant effects on regeneration of the PDL. Additional preclinical evaluation is needed to confirm these initial observations prior to clinical application.

Topics: Alveolar Bone Loss; Animals; Bone Morphogenetic Protein 2; Bone Morphogenetic Proteins; Bone Regeneration; Dental Cementum; Dogs; Humans; Male; Periodontal Ligament; Pilot Projects; Regeneration; Root Resorption; Transforming Growth Factor beta

The results of these studies show that rhBMP-2 clearly enhances regeneration in periodontal defects (Figures 2&3). The extent of regeneration appears to be significantly influenced by the nature of the carrier material used to deliver the rhBMP-2 to the periodontal wound. While the positive effects of rhBMP-2 on osteogenesis are well established, less is known about the way in which rhBMP-2 effects cementogenesis, or its role in the formation of a new periodontal ligament. From the studies reviewed, it would appear that rhBMP-2 facilitate in the formation of cellular cementum on previously denuded root surfaces. This newly formed cementum has also been shown to support an organised periodontal ligament attachment. Mechanisms related to the possible role of rhBMP-2 in ankylosis are presently unclear and will require further investigation as such sequelle may complicate the clinical utility of rhBMP-2 in periodontal regeneration. Root resorption has also been reported in the above mentioned studies and appears to be related to the concentration of rhBMP-2. Further research directed at understanding how different carriers influence the way in which the rhBMP-2 is released during wound healing should assist researchers with how to best apply these bioengineered proteins to ultimately achieve a more predictable regeneration of the periodontal attachment apparatus. Moreover, additional research into the differing biologic effects of other members of the BMP family of proteins may also hold further promise in the application of this technology to periodontal regeneration.

Topics: Animals; Biomedical Engineering; Bone Morphogenetic Protein 2; Bone Morphogenetic Proteins; Bone Regeneration; Cloning, Molecular; Drug Carriers; Guided Tissue Regeneration, Periodontal; Humans; Periodontium; Recombinant Proteins; Root Resorption; Tooth Ankylosis; Transforming Growth Factor beta

To evaluate the expression of TNF-α, IL-6, IFN-γ, TGF-β, IL-4, IL-10, RANKL, RANK and OPG on mouse calvarial bone treated with MTA, Geristore. Bone wounds were made on the heads of C57BL/6 mice, breaking the periosteum and the cortical surface of the calvaria. Each repair agent was inserted into sectioned Eppendorf microtubes and placed on the bone wound, and soft tissues were sutured. At 14 and 21 days, animals were sacrificed and the treated region was dissected. The calvaria bone was removed, and RNA was extracted. mRNA expression of the aforementioned cytokines was assessed using real-time PCR. Data were analysed by nonparametric methods, including the Mann-Whitney and Kruskal-Wallis tests (P < 0.05).. Following treatment with Emdogain. The clinical indication of these repair agents depends on the root resorption diagnosis. Whilst MTA and Emdogain

Topics: Aluminum Compounds; Animals; Calcium Compounds; Cytokines; Dental Enamel Proteins; Drug Combinations; Gene Expression Regulation; Glass Ionomer Cements; Inflammation; Interferon-gamma; Interleukin-10; Interleukin-4; Interleukin-6; Mice; Mice, Inbred C57BL; Osteoprotegerin; Oxides; RANK Ligand; Receptor Activator of Nuclear Factor-kappa B; Resins, Synthetic; RNA, Messenger; Root Resorption; Silicates; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

The progressive forms of inflammatory external root resorption (IERR) and replacement external root resorption (RERR) are serious complications and the main causes of tooth loss after replantation. This study aimed to investigate the expression pattern of inflammatory molecules in extracted human teeth presenting with external root resorption (ERR) after replantation.. Root fragments from 22 teeth showing IERR and 20 teeth with RERR were triturated using a homogenizer to extract inflammatory molecules. Interleukin-1β (IL-1β), IL-1Ra, transforming growth factor beta, IL-8/CXCL8, CCL2, CCL3, and CCL5 were measured using double-ligand enzyme-linked immunosorbent assay, and IL-2, IL-4, IL-6, IL-10, tumor necrosis factor alpha, interferon gamma, and IL-17A detection was performed using the multiplex Th1/Th2/Th17 Cytometric Bead Array kit (BD Biosciences, San Jose, CA). Cytokine and chemokine concentrations were compared in the RERR and IERR groups corrected by patients' age at the moment of extraction, survival time after replantation, and index of ERR, adopting a generalized estimation equation model.. The IERR group showed higher levels of tumor necrosis factor alpha than the RERR group, even after correction for the index of ERR (P < .05). IL-1Ra levels were higher in the IERR group for moderate cases but higher in the RERR group for severe cases (P < .05). IL-4 concentration became higher with the increase of patients' age in the RERR group but did not vary in the IERR group (P < .05). CCL2 levels decreased with the increase of the patients' age at the moment of extraction irrespective of the type or index of ERR (P < .05).. The present results showed differences in the immunologic profile of IERR and RERR that may be relevant to understanding the biological mechanisms underlying ERR.

Topics: Adolescent; Chemokine CCL2; Chemokine CCL3; Chemokine CCL5; Cytokines; Female; Humans; Interferon-gamma; Interleukin 1 Receptor Antagonist Protein; Interleukin-10; Interleukin-17; Interleukin-1beta; Interleukin-2; Interleukin-4; Interleukin-6; Interleukin-8; Male; Root Resorption; Tooth Replantation; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

The present study was performed to examine how transforming growth factor β (TGF-β) in root-surrounding tissues on deciduous teeth regulates the differentiation induction into odontoclasts during physiological root resorption. We prepared root-surrounding tissues with (R) or without (N) physiological root resorption scraped off at three regions (R1-R3 or N1-N3) from the cervical area to the apical area of the tooth and measured both TGF-β and the tartrate-resistant acid phosphatase (TRAP) activities. The TGF-β activity level was increased in N1-N3, whereas the TRAP activity was increased in R2 and R3. In vitro experiments for the receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-mediated osteoclast differentiation revealed that proteins from N1-N3 and R1-R3 enhanced the TRAP activity in RAW264 cells. A genetic study indicated that the mRNA levels of TGF-β1 in N1 and N2 were significantly increased, and corresponded with levels of osteoprotegerin (OPG). In contrast, the expression level of RANKL was increased in R2 and R3. Our findings suggest that TGF-β is closely related to the regulation of OPG induction and RANKL-mediated odontoclast differentiation depending on the timing of RANKL and OPG mRNA expression in the root-surrounding tissues of deciduous teeth during physiological root resorption.

Topics: Animals; NF-kappa B; Osteoclasts; Osteoprotegerin; RANK Ligand; Root Resorption; Swine; Tartrate-Resistant Acid Phosphatase; Tooth, Deciduous; Transforming Growth Factor beta

The ability of the periodontal ligament (PDL) to absorb and distribute forces is necessary for periodontal homeostasis. This adaptive response may be determined, in part, by a key molecule, periostin, which maintains the integrity of the PDL during occlusal function and inflammation. Periostin is primarily expressed in the PDL and is highly homologous to betaig-H3 (transforming growth factor-beta [TGF-beta] inducible gene). Cementum, alveolar bone, and the PDL of periostin-null mice dramatically deteriorate following tooth eruption. The purpose of this study was to determine the role of periostin in maintaining the functional integrity of the periodontium.. The periodontia from periostin-null mice were characterized followed by unloading the incisors. The effect of substrate stretching on periostin expression was evaluated using a murine PDL cell line. Real-time reverse transcription-polymerase chain reaction was used to quantify mRNA levels of periostin and TGF-beta. TGF-beta1 neutralizing antibodies were used to determine whether the effects of substrate stretching on periostin expression are mediated through TGF-beta.. Severe periodontal defects were observed in the periostin-null mice after tooth eruption. The removal of masticatory forces in periostin-null mice rescue the periodontal defects. Periostin expression was increased in strained PDL cells by 9.2-fold at 48 hours and was preceded by a transient increase in TGF-beta mRNA in vitro. Elevation of periostin in response to mechanical stress was blocked by the addition of 2.5 ng/ml neutralizing antibody to TGF-beta1, suggesting that mechanical strain activates TGF-beta to have potential autocrine effects and to increase periostin expression.. Mechanical loading maintains sufficient periostin expression to ensure the integrity of the periodontium in response to occlusal load.

Topics: Alveolar Bone Loss; Ameloblasts; Animals; Autocrine Communication; Biomechanical Phenomena; Bite Force; Cell Adhesion Molecules; Cell Line; Dental Cementum; Fibroblasts; Image Processing, Computer-Assisted; Immunohistochemistry; Mice; Mice, Knockout; Mice, Transgenic; Periodontal Attachment Loss; Periodontal Ligament; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Root Resorption; Stress, Mechanical; Tomography, X-Ray Computed; Tooth Eruption; Transforming Growth Factor beta; Transforming Growth Factor beta1

Recent studies have shown that bone morphogenetic protein-2 (BMP-2) stimulates mineralization and osteoclast differentiation. Osteoclastic resorption by BMP-2 application may play an important role in the regulation of new cementum-like tissue formation on the dentin surfaces. Therefore, this study aimed to examine the effect of BMP-2 application on dentin resorption and cementum-like tissue formation at the dentin surfaces.. Seventy-two flat dentin blocks were prepared from rat roots and treated with 24% EDTA. Each block was assigned to group 0, group 100, or group 400, and immersed correspondingly in 0, 100, or 400 microg/ml BMP-2. The dentin blocks were then implanted into palatal connective tissue of rats, and specimens were prepared 2, 4 and 8 wk after surgery for histologic and histomorphometric analyses.. BMP-2 caused a dose-dependent increase in dentin resorption by osteoclastic cells. New cementum-like tissue was randomly formed on parts of the nonresorbed and resorbed dentin surfaces in groups 100 and 400. Dentin resorption in groups 100 and 400 was significantly greater than group 0 (p < 0.01). However, at 8 wk, new cementum-like tissue formed in 41.8% of group 100, as compared with 16.2% of group 400 (p < 0.05).. Dentin resorption was stimulated by a high dose of BMP-2, and cementum-like tissue was induced by a low dose of BMP-2, effectively suggesting that BMP-2 application, at an appropriate dose, to a dentin surface may enhance periodontal regeneration.

Topics: Animals; Bone Morphogenetic Protein 2; Bone Morphogenetic Proteins; Cementogenesis; Dentin; Dose-Response Relationship, Drug; Immunoenzyme Techniques; Male; Osteoclasts; Rats; Rats, Wistar; Regeneration; Root Resorption; Statistics, Nonparametric; Transforming Growth Factor beta

Subcutaneous and intramuscular implants of bone morphogenetic protein-12 (BMP-12) have been shown to induce formation of tendon and ligament tissue. BMP-12 induced a new attachment with a distinct fibrocartilaginous zone at the tendon-bone interface in the rat tendon-bone attachment model. Surgical controls showed poor healing and failure to reform the appropriate tendon-bone attachment morphologically. Application of recombinant human BMP-12 (rhBMP-12) to periodontal defects suggests that rhBMP-12 has the potential to support regeneration of the periodontal ligament (PDL). The objective of this pilot study was to evaluate this effect of rhBMP-12 in a tooth replantation model.. Six, young adult, male Hound Labrador mongrel dogs were used. Maxillary and/or mandibular incisor and premolar teeth were extracted and the PDL was either left "intact" or removed by root planing. rhBMP-12 (1.0 mg/ml) or a buffer control was topically applied to teeth with "intact" PDL in contralateral jaw quadrants in each of 3 animals. The teeth were immersed in 1.0 ml of the rhBMP-12 or the buffer solution for 10 min and then replanted. The remaining three animals received rhBMP-12 (1.0 mg/ml) and the buffer control in a similar fashion applied to teeth instrumented to remove the PDL and cementum, and surface demineralized with citric acid. The animals were euthanized at 8 weeks postsurgery and block sections were collected and processed for histopathologic analysis.. No dramatic differences were found between teeth receiving topical rhBMP-12 and the buffer control. Application of rhBMP-12 did not have an apparent effect on new cementum and PDL formation in the tooth replantation model. Moreover, application of rhBMP-12 did not increase nor did it decrease the apparent presence and extent of ankylosis along the root surface compared to the control.. The observations from this study do not support the use of topical rhBMP-12 to support the reestablishment of the PDL including regeneration of cementum and functionally oriented fibers, and to prevent ankylosis and root resorption following replantation of teeth.

Topics: Animals; Bone Morphogenetic Protein 2; Bone Morphogenetic Proteins; Combined Modality Therapy; Dogs; Humans; Male; Periodontal Attachment Loss; Periodontal Ligament; Pilot Projects; Rats; Root Resorption; Tooth Ankylosis; Tooth Replantation; Transforming Growth Factor beta

Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been shown to induce clinically relevant bone formation for orthopedic, craniofacial, and oral indications. It appears critical, in particular for onlay indications, that the associated carrier technology exhibits structural integrity to offset compressive forces in support of rhBMP-2-induced bone formation. The objective of this study was to evaluate a calcium phosphate (CP) cement, Ceredex, as a candidate carrier for rhBMP-2 in a defect model with limited osteogenic potential.. Bilateral, critical size, 6-mm, supra-alveolar, periodontal defects were created in six, adult, male, Hound Labrador mongrels. Three animals received rhBMP-2/Ceredex (rhBMP-2 at 0.20 and 0.40 mg/ml) in contralateral defect sites (implant volume/defect approximately 1 ml). One defect site in each of the three remaining animals received Ceredex without rhBMP-2 (control). The animals were euthanized at 12 weeks postsurgery for histologic and histometric analysis.. Mean induced bone height exceeded 80% of the defect height for supra-alveolar periodontal defects receiving rhBMP-2/Ceredex without major differences between rhBMP-2 concentrations compared with approximately 40% for the control. The newly formed bone, a mixture of lamellar and woven bone in fibrovascular tissue, circumscribed relatively large portions of the residual Ceredex biomaterial. Inflammatory lesions were associated with limited bone formation in some sites. From a periodontal perspective, sites receiving rhBMP-2/Ceredex exhibited increased cementum formation compared with control, but without a functionally oriented periodontal ligament, and increased ankylosis and root resorption. Control sites exhibited early wound failure and exposure, loss of the Ceredex biomaterial, and limited bone formation.. The Ceredex CP cement appears a potentially promising carrier technology for rhBMP-2 onlay indications. However, a slow resorption rate may prevent its wider use. This study does not support use of the rhBMP-2/Ceredex combination for periodontal indications.

Topics: Absorbable Implants; Animals; Bone Morphogenetic Protein 2; Bone Morphogenetic Proteins; Bone Regeneration; Calcium Phosphates; Cementogenesis; Dental Cements; Dogs; Drug Carriers; Furcation Defects; Humans; Male; Oral Surgical Procedures; Recombinant Proteins; Root Resorption; Tooth Ankylosis; Transforming Growth Factor beta

To clarify the roles of epithelial cell rests of Malassez (ECRM) during periodontal repair, experimental root resorption was induced in rats and then the ECRM that existed in periodontal ligament during cementum repair was investigated using morphological and immunohistochemical approaches. At day 7, after mechanical injury, root resorption was observed and ECRM were present adjacent to the site of resorption lacunae. They were observed in periodontal ligament adjacent to site of the resorption lacunae. These ECRM were immunoreactive for bone morphogenetic protein-2. During the stage of early cementum repair, the ECRM were immunoreactive for osteopontin and ameloblastin. They strongly reacted to proliferating cell nuclear antigen. In uninjured control sections, ECRM located in the periodontal ligament adjacent to cementum were not immunoreactive for any antibodies. These findings suggested that ECRM may be related to cementum repair by activating their potential to secrete matrix proteins which have been expressed in tooth development.

Topics: Amelogenin; Animals; Antibodies; Bone Morphogenetic Protein 2; Bone Morphogenetic Proteins; Coloring Agents; Dental Cementum; Dental Enamel Proteins; Epithelial Cells; Immunoenzyme Techniques; Immunohistochemistry; Leukocytes; Macrophages; Male; Osteopontin; Periodontal Ligament; Phosphoproteins; Proliferating Cell Nuclear Antigen; Rats; Rats, Wistar; Root Resorption; Sialoglycoproteins; Transforming Growth Factor beta; Wound Healing

Recombinant human bone morphogenetic protein-2 (rhBMP-2) in a proper carrier has been shown to induce clinically relevant bone formation for several oral/maxillofacial and periodontal indications and to stimulate regeneration of the periodontal attachment. The objective of this study is to evaluate regeneration of alveolar bone, cementum, periodontal ligament, and associated root resorption and ankylosis following surgical implantation of rhBMP-2 in an absorbable collagen sponge (ACS) or a calcium phosphate putty (alphaBSM) carrier in 3-wall intrabony periodontal defects in the baboon.. rhBMP-2/ACS and rhBMP-2/alphaBSM were implanted in surgically produced, maxillary and mandibular, large size, 3-wall intrabony defects in 4 baboons. Contralateral jaw quadrants were implanted with buffer/ACS, buffer/ alphaBSM, or served as sham-operated surgical controls. Treatments were allocated to left and right, maxillary and mandibular, jaw quadrants following a randomization schedule. Four months following implantation, block biopsies of defect sites were obtained, processed, and subjected to histologic and histometric analysis.. Defect sites receiving rhBMP-2/ACS and rhBMP-2/alphaBSM demonstrated significantly greater regeneration than controls. No significant differences were observed between defect sites receiving rhBMP-2/ACS or rhBMP-2/alphaBSM regarding epithelial migration and connective tissue attachment and new bone formation. However, rhBMP-2/ACS supported significantly greater new cementum formation. Ankylosis or root resorption were not observed.. The results of this study support the use of rhBMP-2 to enhance periodontal regeneration of intrabony periodontal defects. While this novel technology holds promise, refinement in carrier systems may provide the key to enhancement of the regenerative potential.

Topics: Alveolar Bone Loss; Analysis of Variance; Animals; Bone Morphogenetic Protein 2; Bone Morphogenetic Proteins; Bone Regeneration; Calcium Phosphates; Cementogenesis; Collagen; Drug Carriers; Drug Implants; Humans; Oral Surgical Procedures; Papio; Periodontal Ligament; Postoperative Care; Recombinant Proteins; Regeneration; Root Resorption; Tooth Ankylosis; Transforming Growth Factor beta

Recombinant human bone morphogenetic protein-2 (rhBMP-2) in an absorbable collagen sponge (ACS) carrier is being evaluated as a candidate therapy for periodontal regeneration. The objective of this study was to evaluate regeneration of alveolar bone and cementum, and associated root resorption and ankylosis following surgical implantation of rhBMP-2/ACS in a canine clinical model.. Bilateral 3-wall intrabony periodontal defects were surgically induced in the premolar region in the maxilla and mandible in 8 young adult Korean mongrel dogs. The defects in each animal received rhBMP-2/ACS (rhBMP-2 at 0.2 mg/ml, total implant volume/defect approximately 0.1 ml) or buffer/ACS, or served as sham-operated controls. Surgeries were sequenced for each animal to provide postmortem observations following 8- and 24-week healing intervals. Treatment outcomes were evaluated using clinical, radiographic, and histometric parameters.. Surgical implantation of rhBMP-2/ACS resulted in accelerated enhanced bone formation in the 3-wall intrabony periodontal defects but in no apparent enhancement of cementum regeneration. rhBMP-2/ACS did not appear to be associated with aberrant healing events such as root resorption and ankylosis under these simulated clinical conditions.. Surgical implantation of rhBMP-2/ACS may be used safely to support regeneration of alveolar bone in intrabony periodontal defects in dogs without aberrant events such as root resorption or ankylosis complicating the regenerative procedure. rhBMP-2/ACS does not appear to have a significant effect on cementum regeneration and formation of a functional periodontal ligament in this model.

Topics: Alveolar Bone Loss; Alveolar Process; Analysis of Variance; Animals; Bone Morphogenetic Protein 2; Bone Morphogenetic Proteins; Bone Regeneration; Connective Tissue; Dental Cementum; Dogs; Drug Carriers; Drug Implants; Epithelial Attachment; Follow-Up Studies; Gelatin Sponge, Absorbable; Humans; Osteogenesis; Periodontal Ligament; Radiography; Recombinant Proteins; Root Resorption; Statistics as Topic; Tooth Ankylosis; Transforming Growth Factor beta; Wound Healing

The purpose of this preliminary study was to examine experimental tooth movement into newly generated bone induced by recombinant human bone morphogenetic protein-2 (rhBMP-2).. After extraction of the maxillary first premolars, bone defects were surgically created in eight adult beagle dogs using a 5-mm-diameter trepan bar. According to which material was grafted into the bone defects, animals were divided into the following four groups: (1) the rhBMP-2 group in which rhBMP-2 with a poly[ D,L-(lactide-co-glycolide)]/gelatin sponge complex was implanted; (2) the spongiosa group in which spongiosa from the tibia was grafted; (3) the nongrafted group in which no material was embedded; and (4) the control group in which only tooth extraction was performed. The osteoinductive activity of rhBMP-2 and tooth movement into the newly generated bone were examined by histological and morphometric comparisons of each group.. Considerable new bone formation was observed at the grafted site both in the rhBMP-2 and in the spongiosa groups. The area of generated bone in the rhBMP-2 group was significantly greater than that in the spongiosa group. Newly generated bone, in both the rhBMP-2 and spongisosa groups, showed a similar histological response to orthodontic force as in normal alveolar bone in the control group. However, root resorption occurred on the pressure side in the rhBMP-2 group.. These results indicated that rhBMP-2 might constitute an alternative material to autogeneous bone grafting for alveolar cleft defects. Further studies regarding tooth movement into generated bone induced by rhBMP-2 are suggested.

Topics: Absorbable Implants; Alveolar Bone Loss; Alveolar Process; Animals; Biocompatible Materials; Bone Morphogenetic Protein 2; Bone Morphogenetic Proteins; Bone Regeneration; Bone Transplantation; Dogs; Female; Humans; Implants, Experimental; Lactic Acid; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Polymers; Recombinant Proteins; Root Resorption; Tooth Movement Techniques; Transforming Growth Factor beta

The objective of this study was to evaluate the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) concentration on regeneration of alveolar bone and cementum, and on associated root resorption and ankylosis. Contralateral, critical size, supra-alveolar, periodontal defects were surgically produced and immediately implanted with rhBMP-2 in an absorbable collagen sponge (ACS) carrier in 8, young adult, male, beagle dogs. 6 animals received rhBMP-2/ACS (rhBMP-2 at 0.05, 0.10, or 0.20 mg/mL; total construct volume/defect approximately 4.0 mL) in contralateral defects following an incomplete block design. 2 animals received rhBMP-2/ACS (rhBMP-2 at 0 and 0.10 mg/mL) in contralateral defects (controls). The animals were euthanised at 8 weeks post-surgery and block sections of the defects were collected for histologic and histometric analysis. Supra-alveolar periodontal defects receiving rhBMP-2 at 0.05, 0.10, or 0.20 mg/ml exhibited extensive alveolar regeneration comprising 86%, 96%, and 88% of the defect height, respectively. Cementum regeneration encompassed 8%, 6%, and 8% of the defect height, respectively. Root resorption was observed for all rhBMP-2 concentrations. Ankylosis was observed in almost all teeth receiving rhBMP-2. Control defects without rhBMP-2 exhibited limited, if any, evidence of alveolar bone and cementum regeneration, root resorption, or ankylosis. Within the selected rhBMP-2 concentration and observation interval, there appear to be no meaningful differences in regeneration of alveolar bone and cementum. There also appear to be no significant differences in the incidence and extent of root resorption and ankylosis, though there may be a positive correlation with rhBMP-2 concentration.

Topics: Absorbable Implants; Alveolar Bone Loss; Animals; Bone Morphogenetic Protein 2; Bone Morphogenetic Proteins; Bone Regeneration; Cattle; Collagen; Dental Cementum; Dental Implantation, Endosseous; Dental Implants; Dogs; Humans; Implants, Experimental; Male; Mandible; Periodontal Attachment Loss; Recombinant Proteins; Regeneration; Root Resorption; Tooth Ankylosis; Transforming Growth Factor beta